This is not an X-challenge engine. This is the likely the old F650gs engine with different coloured casings.

Okay, I'll offer that it isn't an X-challenge engine, but it absolutely-certainly is not the old F650GS engine. Evidence observed on the LHS engine case cover. The cover matches the X-Challenge design or is at least very similar. Note the clutch cover can be removed without having to remove the whole case cover.

When the G650GS was release I read that the engine was the G650 engine, as in the engine from the X-line of bikes that was phased out of production. This seemed to be the case as the engines looked identical right down to the paint. The new release shows the paint has changed but the engine looks the same to me.